There are many applications where a high energy power source would be desirable, even if the energy is produced for only a short period of time, in which the power source is of very small size and simple design. For example, such a power source may be utilized to initiate longer term or other higher energy power sources, such as normally deactivated batteries, which require some initiation energy to begin operation. Other applications include the remote detonation of explosives, the setting off of an alarm or generating a penalty should an unauthorized intrusion occur in a secured area or container, or the like. It would be desirable in these applications that the power source be energizable by some relatively simple mechanism which in itself does not require any appreciable energy to be initiated. In addition, such a power source should be relatively insensitive to environmental conditions to which it may be subjected both before and during operation.